Bag stacker

ABSTRACT

A bag-collecting device for use at the delivery end of a bagmaking machine comprising, in combination, two bag-collecting platens assembled in vertically spaced substantially parallel relationship, each of said platens having a front end and a rear end being coextensive with the other platen at its front end, and means for supporting the platens and reciprocatably moving at least the front ends of said platens between two vertically spaced positions whereby the two platens can be brought into alternative registration with the delivery end of the bagmaking machine, said means for reciprocatably moving the front end of the platens being automatically responsive to a bag counter unit.

United States Patent [72] Inventor John Worndl Brampton, Ontario, Canada1211 Appl. No. 865,735 [22] Filed Oct. 13,1969 [45] Patented Aug. 10,1971 {73] Assignee Canadian Industries Limited Montreal, Quebec, Canada[32] Priority Oct. 30, 1968 [33] Canada 033,960

[54] BAG STACKER Primary Examiner-Gerald M. Forlenza Assistant ExaminerRobert J. Spar Attorney-Guy Drouin 7 ABSTRACT: A bag-collecting devicefor use at the delivery end of a bagmaking machine comprising, incombination, two 2 Chins 3 Figs' bag-collecting platens assembled invertically spaced substan- [52] US. Cl. 214/6 D, tially parallelrelationship, each of aid platens having a front 2 271/36 end and a rearend being coextensive with the other platen at [51] lnt.Cl. B65g 57/11 if m d, d means for supporting the platens and [50] FQHOSCII'CII 214/6 H,6 recip matably moving at least the front ends of said platens 6 6271/86, 64, 88 between two vertically spaced positions whereby the twoplatens can be brought into alternative registration with the [56]References CM delivery end of the bagmaking machine, said means forUNITED TATE PA reciprocatably moving the front end of the platens beingauto- 2,093.992 9/ 1937 Braam 271/64 matically responsive to a bagcounter unit.

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I 1 J1 :r 1X1 f/Wrll IJ Z3 3 24 x2 24 STOP\. 4 5 20 START o E/ 29 2 p we22 3/ gd ao /9-- s 1 I I s z 28 2/ 2 25 2 PATENTEUAUGIOIQYI $598,253SHEET 1 BF 2 John WORNDL BAG STACKER This invention relates to anapparatus for collecting bags at the delivery end of a bag-makingmachine.

Bags are produced from plastic sheeting or tubular film on various typesof bag-making machines which basically heatseal the sheeting or film inthe form of bags and then cut the bags into individual units. These bagsare then delivered to the end of the machine where they are counted,stacked and packaged. Y

The constantly increasing demand of recent years for plastics bags hasinduced manufacturers into designing bagmaking machines with a muchhigher output than heretofore. Such a higher output is achieved throughhigher speeds and through wider machines which form more than one bag ata time from multiple-webstreams. While these machines are successful inso far as the output is concerned, they present a certain difficulty attheir delivery end where the finished bags must be collected. Variouscollecting devices have been proposed to automatically count and stackthe finished bags, but these devices suffer from the disadvantagesthat'they do not allow one employee to handle more than one web and donot permit the handling of bags of variable sizes.

It is the primary object of this invention to provide a bagcollectingapparatus or bag stacker which is free of the above disadvantages.Additional objects of the invention will appear hereinafter. v

Generally speaking, the invention resides in a bag stacker for use atthe delivery end of a bag-makingmachine and comprises a frame and twovertically spaced platens supported by said frame, each platen having abag-receiving end and a bag delivery end and being actuatable by apneumatic cylinder in such a way that at least its bag-receiving end isreciprocatably and verticallymovable between two predeterminedpositions,said cylinder being responsive to a timer and bag counter unit.

The specific features and advantages of the apparatus ofthe inventionwill become apparent as the following description of the inventionprogresses, reference being made to the accompanying drawings wherein: Y

FIG. 1 is a plan view of a specific embodiment of the apparatus of theinvention;

FIG. 2 is a front elevation of the same embodiment and FIG. 3 is a sideelevation of still the same embodiment.

The bag stacker illustrated in the drawings is one which is particularlyadapted .foruse in connection with a bag-making machine producing fourbags at a time. This specific bag stacker is comprised of abag-collecting assembly supported on a frame generally indicated at 11.

The bag-collecting assembly 10 consists of two platens l2 and 13arranged in spaced, generally parallel relationship and held together bymeans of spacers 14 fixed on their longitudinal sides. Both platens arecoextensive at their front ends, that is at the ends which, when thestacker is in use, come into abutment with the delivery end of thebag-making machine. At their rear ends, the platens are staggered withthe top platen l3 terminating short of the bottom platen 12 in order topermit easy removal of the bags from said bottom platen.

Each of the platens 12 and 13 is provided at its rear end with atelescopingly slidable extensions 15 which can be drawn outwardly asdesired to increase the effective length of the platen for accommodatingbags ofdifferent lengths. Each slidable cxtension 15 has at its free endan upstanding flange l6 acting as a stopper for the bags, and aplurality of handholes 17 for easy grabbing of the bags from the platen.

The frame 11 is a rigid structure comprised of two rear legs 18 and 19and one front leg 20, said rear legs and front leg being held togetherby means of cross bars 21 and braces 22. The rear legs are located indirectly opposite relationship, one on each of the longitudinal sides ofthe platens adjacent the rear end thereof. Each of said rear legs 18 and19 is provided at its top with a rigidly secured extension 23 having apin 24 projecting inwardly of the frame structure. The set ofconfronting pins so provided constitutes the support for the rear end ofthe assembly of platens and the portions of the extensions 23 projectingabove the pins act as guides for maintaining the platens in properposition. It can be readily appreciated from the above arrangement thatthe rear end'of the platen 12 is only allowed to rest on the pin 24 andthat the assembly of platens is thus free to pivot on said pins.

The front leg 20 is located substantially midway between the twolongitudinal side of the platens adjacent the front end thereof andcomprises a hydraulic cylinder 25v having it bottom end hinged on thetop end of a short post 26. The hydraulic cylinder has a piston rod 27the free end of which is hingedly connected to the underside of thebottom platen 12 at a point generally located on the prolonged-axis ofthe short post 26.

As shown in FIGS. 2 and 3, the frontleg 20 and rear legs 18 and 19 mayadvantageously be provided with leveling screw 28. The hydrauliccylinder operates through an electrical circuit comprising a bag counter29, a timer 30, a four way double solenoid valve 31 and a set ofswitches LS-l, LS-2 and LS-3 actuatable by a cam 32 borne on the pistonrod, to raise and lower the assembly of bag-collecting platens atregular intervals and to alternately bring the platens l2 and 13 intoregistration with the delivery end of the bag-making making machine. 1

As indicated hereinbefore, the bag stacker particularly shown in thedrawings is for use with a machine producing four'bags at a time. inorder to accommodate such a machine, each platen is divided into fourindividual bag-receiving spaces by metal dividers 33. Each of said fourindividual spaces is .provided longitudinally and centrally thereof,with a bar 34 which affords a better flow of the bags down the platensto the upstanding flanges or end stops 16. Although the dividers 33 andbars 34 could be fixed on the platens in a permanent manner, it has beenfound most advantageous to have them adjustable. The dividers and barsillustrated in the drawings are thus held on the platens by magnets sothat they can be arranged to suit bag-making machines making bags fromany number of film webs.

In operation, the bag stacker is placed in such a way that the front endof one of the platens, for example platen 13, is in registration withthe delivery end of the bag-making machine. The dividers 33, bars 34 andplaten extensions 15 are then adjusted to suit the number of film webson the bag-making machine as well asthe dimensions of the finished bags.

Once bag production has started, the finished bags flow onto platen 13over the bars 34 and into the individual spaces delimited by thedividers 33to the end stops 16. As the bags flow ad are stacked ontoplaten 13, they are counted by automatic counter 29. Once apredetermined count has been reached, the second platen 12 isautomatically pivoted up in o place by means of the cylinder 25. Anoperator can now remove the bags from the first platen 13, using thehandholes 17. The bags are thus in stacks of a definite count and can bepackaged in any of the usual methods. While platen 13 is being unloaded,the second platen 12 is stacking bags to the predetermined count and,upon completion, the cylinder pivots platen 13 down in to collectingposition and platen 12 can now be unloaded.

The automatic operation of cylinder 25 is as follows. When thedetermined number of bags has been reached on one of the platens, thecounter 29 activates the adjustable timer 30 which synchronizes theindexing of the platens with bag delivery. After the set time, the timer30 energizes one side of the four-way double solenoid valve 31 throughlimit switch LS-l which is held closed by the'cam 32 on the piston rod27. The four-way valve shifts, raising the piston rod 27 of the cylinder25. Halfway through the stroke, limit switch LS-2 is opened momentarilyby the cam 32 resetting the timer. At the end of the piston stroke thecam 32 closes limit switch LS-3 placing the opposite solenoid in'thecircuit. The hydraulic cylinder is now ready for another cycle.

While the invention has been described in connection with a specificembodiment in which the front end only of the bagcollecting platens isreciprocatable between two vertically spaced positions, it should beunderstood that it is capable of many modifications. Changes, therefore,in the construction and arrangement may be made without departing fromthe spirit and scope of the invention as disclosed. It is easy to think,for instance, of an arrangement whereby the assembly of platens could betotally reciprocably raised and lowered rather than at its front endonly.

What 1 claim is:

l. A bag-collecting device for use at the delivery end of a bag-makingmachine comprising, in combination:

A. Two bag-collecting platens, each having a front end and a rear endand being coextensive with the other platen at its front end, and eachcomprising:

a. at its rear end, a telescopingly slidable extension the free end ofwhich has an upstanding flange acting as as a stopper for the bag,

b. magnetically held and adjustable dividers forming on said platen amember of longitudinal spaces corresponding to the number of bagsproduced at the same time by the bag-making machine, and

c. magnetically held and adjustable bars located centrally andlongitudinally of the spaces between said dividers to permit better flowof the bags in said spaces; and

B. Means for supporting said platens and reciprocably moving at leastthe front ends thereof between two vertically spaced positions wherebythe two platens can be brought into alternative registration with thedelivery end of the bag-making machine, said means being automaticallyresponsive to a bag counter unit.

2. A device according to claim 1, wherein the means for supporting theplatens and reciprocatably moving the front end of said platens betweentwo vertically spaced positions consists essentially ofa framecomprising means for pivotably supporting the rear end of said platensand a hydraulic cylinder for supporting the front end of said platens,said cylinder being mounted vertically with one end hinged to theunderside of the lower platen and the other end hinged to said frame.

1. A bag-collecting device for use at the delivery end of a bagmakingmachine comprising, in combination: A. Two bag-collecting platens, eachhaving a front end and a rear end and being coextensive with the otherplaten at its front end, and each comprising: a. at its rear end, atelescopingly slidable extension the free end of which has an upstandingflange acting as a stopper for the bag, b. magnetically held andadjustable dividers forming on said platen a member of longitudinalspaces corresponding to the number of bags produced at the same time bythe bag-making machine, and c. magnetically held and adjustable barslocated centrally and longitudinally of the spaces between said dividersto permit better flow of the bags in said spaces; and B. Means forsupporting said platens and reciprocably moving at least the front endsthereof between two vertically spaced positions whereby the two platenscan be brought into alternative registration with the delivery end ofthe bagmaking machine, said means being automatically responsive to abag counter unit.
 2. A device according to claim 1, wherein the meansfor supporting the platens and reciprocatably moving the front end ofsaid platens between two vertically spaced positions consistsessentially of a frame comprising means for pivotably supporting therear end of said platens and a hydraulic cylinder for supporting thefront end of said platens, said cylinder being mounted vertically withone end hinged to the underside of the lower platen and the other endhinged to said frame.